Add guest cart drawer, Continue handoff, and shared customer login.

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/site.ts

@@ -1,16 +1,22 @@
-export const DOMAIN = "salarstore.com";
+export const DOMAIN = process.env.NEXT_PUBLIC_DOMAIN || "salarstore.com";
 
 export const API = {
-  base: "https://api.meshkee.com/api/v1",
+  base: process.env.NEXT_PUBLIC_API_BASE_URL?.replace(/\/$/, "") || "https://api.meshkee.com/api/v1",
   domain: DOMAIN,
 };
 
+export const CUSTOMER_ORIGIN =
+  process.env.NEXT_PUBLIC_CUSTOMER_ORIGIN?.replace(/\/$/, "") || `https://customer.${DOMAIN}`;
+
+export const BUSINESS_ORIGIN =
+  process.env.NEXT_PUBLIC_BUSINESS_ORIGIN?.replace(/\/$/, "") || `https://business.${DOMAIN}`;
+
 export const SITE = {
   nameFa: "سالار استور",
   nameEn: "SALAR STORE",
   tagline: "فروشگاه لوازم ورزشی و کوهنوردی",
   domain: DOMAIN,
-  customerUrl: `https://customer.${DOMAIN}`,
+  customerUrl: CUSTOMER_ORIGIN,
   phone: "09127491700",
   phoneDisplay: "0912 749 1700",
   address: "قم، بسیج (هنرستان)، نبش کوچه ۹",